when "Generate PDF and Attach" activity is called all attachments in current case are being attached and sent to email
SCENARIO: when "GeneratePDFandAttach" method is called in an activity (for second time), only one attachment is to be attached, but all attachments which are attached to current case ((say) previously generated pdf in the same case(when "GeneratePDFandAttach" is called for first time in flow action, signature.png) are also being sent to email as attachments.